YaVaughnie Wilkins put up a three-story-tall sign near Times Square in New York City with a photo of her and Charles E. Phillips of Oracle. He admits he had a lengthy affair with her. ﻿

SAN FRANCISCO — A prominent Silicon Valley executive with ties to the Obama administration has admitted to an extramarital affair after his jilted mistress plastered romantic pictures of the two of them on giant billboards in three major U.S. cities.

"I had an 8 1/2-year serious relationship with YaVaughnie Wilkins," said Charles E. Phillips, co-president of Oracle Corp. and a member of President Barack Obama's Economic Recovery Advisory Board. "The relationship with Ms. Wilkins has since ended, and we both wish each other well."

Wilkins, a writer and actor, this past week put up a three-story-tall sign near Times Square in New York City with a photo of Wilkins and Phillips hugging and beaming. The sign also quoted Phillips saying to Wilkins: "You are my soulmate forever."

The revelation of a high-tech executive's extramarital affair would not usually capture the public's attention. But the eye-popping way in which this affair was revealed did. The billboards were first spotted by the Gawker blog and then turned up on the cover of the New York Post, which began the story with "Hell hath no fury like a woman scorned — and then there's this lady."

The billboards that also appeared in Atlanta and San Francisco have been taken down. Wilkins, who lives in the Bay Area in California, could not be reached for comment.

The unusual stunt shocked the insular high-tech community that tends to keep quiet about personal indiscretions. Oracle chief executive Larry Ellison, a legendary businessman known for his aggressive business practices and colorful lifestyle, is one of the few flamboyant figures in Silicon Valley.

Ellison recruited Phillips, a Marine with a military upbringing and star Wall Street analyst with degrees in business and law, in 2003. Phillips quickly rose through the ranks, emerging as the public face of the technology giant and a contender to succeed Ellison. He is one of the highest-paid executives in Silicon Valley who is not a chief executive, pulling down $800,000 in salary and taking home nearly $20 million in 2009. He owns more than $80 million in Oracle stock and sits on high-profile boards, including Oracle and Viacom Inc.

Oracle, based in Redwood City, Calif., did not respond to requests for comment. Phillips is slated to lead a meeting for industry analysts this coming week to discuss the company's $7.4 billion merger with Sun Microsystems. A source close to the situation said Phillips would attend, signaling that Oracle is standing by Phillips.

Phillips' wife, Karen, filed for divorce in February 2008. The New York Post says the couple recently reconciled.